Justin Bieber Naked

Justin Bieber Naked

Justin Bieber Naked

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(CelebNMusic247-News) Justin Bieber Naked?

Justin Bieber is wise enough to know when a gift needs givin’ … but he didn’t have a box — so he covered his junk with a guitar and jammed out a naked serenade for one lucky lady fan — HIS GRANDMA!

TMZ has obtained photos of a completely nude Justin Bieber strumming away on his big wooden instrument … at his grandmother’s home in Toronto during Canadian Thanksgiving back in October 2012. And why, you ask, did Bieber go ass naked for g-ma?

Justin-Bieber-Naked-edit-812-2 Our sources tell us JB had been staying at his granny”s house during the holiday … and slept in a little too late on Thanksgiving morning.

Justin Bieber finally woke up after hearing family and friends stirring around the house — so he thought he’d prank ‘em … by grabbing his guitar and playing a naked set a la Jenny from “Forrest Gump” (‘memba that?). We’re told birthday-suited Bieber went right up to his grandma and started belting out some impromptu lyrics … like:

“I Loooove you grandmaaaa … how are youuuu … helloooo grandma.”

We’re told G thought it was pretty funny — and everyone in the home was cracking up — but granny begged the pop star to get back in his room to put some damn clothes on, stat. Canadian Thanksgiving — they go balls out up there.